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<a name="gdk3-Cairo-Interaction"></a><div class="titlepage"></div>
<div class="refnamediv"><table width="100%"><tr>
<td valign="top">
<h2><span class="refentrytitle"><a name="gdk3-Cairo-Interaction.top_of_page"></a>Cairo Interaction</span></h2>
<p>Cairo Interaction — Functions to support using cairo</p>
</td>
<td class="gallery_image" valign="top" align="right"></td>
</tr></table></div>
<div class="refsect1">
<a name="gdk3-Cairo-Interaction.functions"></a><h2>Functions</h2>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="functions_proto_type">
<col class="functions_proto_name">
</colgroup>
<tbody>
<tr>
<td class="function_type">
<a href="/usr/share/gtk-doc/html/cairo/cairo-cairo-surface-t.html#cairo-surface-t"><span class="returnvalue">cairo_surface_t</span></a> *
</td>
<td class="function_name">
<a class="link" href="gdk3-Cairo-Interaction.html#gdk-window-create-similar-surface" title="gdk_window_create_similar_surface ()">gdk_window_create_similar_surface</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<a href="/usr/share/gtk-doc/html/cairo/cairo-cairo-surface-t.html#cairo-surface-t"><span class="returnvalue">cairo_surface_t</span></a> *
</td>
<td class="function_name">
<a class="link" href="gdk3-Cairo-Interaction.html#gdk-window-create-similar-image-surface" title="gdk_window_create_similar_image_surface ()">gdk_window_create_similar_image_surface</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<a href="/usr/share/gtk-doc/html/cairo/cairo-cairo-t.html#cairo-t"><span class="returnvalue">cairo_t</span></a> *
</td>
<td class="function_name">
<a class="link" href="gdk3-Cairo-Interaction.html#gdk-cairo-create" title="gdk_cairo_create ()">gdk_cairo_create</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">gboolean</span>
</td>
<td class="function_name">
<a class="link" href="gdk3-Cairo-Interaction.html#gdk-cairo-get-clip-rectangle" title="gdk_cairo_get_clip_rectangle ()">gdk_cairo_get_clip_rectangle</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<a class="link" href="GdkDrawingContext.html" title="GdkDrawingContext"><span class="returnvalue">GdkDrawingContext</span></a> *
</td>
<td class="function_name">
<a class="link" href="gdk3-Cairo-Interaction.html#gdk-cairo-get-drawing-context" title="gdk_cairo_get_drawing_context ()">gdk_cairo_get_drawing_context</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">void</span>
</td>
<td class="function_name">
<a class="link" href="gdk3-Cairo-Interaction.html#gdk-cairo-set-source-color" title="gdk_cairo_set_source_color ()">gdk_cairo_set_source_color</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">void</span>
</td>
<td class="function_name">
<a class="link" href="gdk3-Cairo-Interaction.html#gdk-cairo-set-source-rgba" title="gdk_cairo_set_source_rgba ()">gdk_cairo_set_source_rgba</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">void</span>
</td>
<td class="function_name">
<a class="link" href="gdk3-Cairo-Interaction.html#gdk-cairo-set-source-pixbuf" title="gdk_cairo_set_source_pixbuf ()">gdk_cairo_set_source_pixbuf</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">void</span>
</td>
<td class="function_name">
<a class="link" href="gdk3-Cairo-Interaction.html#gdk-cairo-set-source-window" title="gdk_cairo_set_source_window ()">gdk_cairo_set_source_window</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">void</span>
</td>
<td class="function_name">
<a class="link" href="gdk3-Cairo-Interaction.html#gdk-cairo-rectangle" title="gdk_cairo_rectangle ()">gdk_cairo_rectangle</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">void</span>
</td>
<td class="function_name">
<a class="link" href="gdk3-Cairo-Interaction.html#gdk-cairo-region" title="gdk_cairo_region ()">gdk_cairo_region</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<a href="/usr/share/gtk-doc/html/cairo/cairo-Regions.html#cairo-region-t"><span class="returnvalue">cairo_region_t</span></a> *
</td>
<td class="function_name">
<a class="link" href="gdk3-Cairo-Interaction.html#gdk-cairo-region-create-from-surface" title="gdk_cairo_region_create_from_surface ()">gdk_cairo_region_create_from_surface</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<a href="/usr/share/gtk-doc/html/cairo/cairo-cairo-surface-t.html#cairo-surface-t"><span class="returnvalue">cairo_surface_t</span></a> *
</td>
<td class="function_name">
<a class="link" href="gdk3-Cairo-Interaction.html#gdk-cairo-surface-create-from-pixbuf" title="gdk_cairo_surface_create_from_pixbuf ()">gdk_cairo_surface_create_from_pixbuf</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">void</span>
</td>
<td class="function_name">
<a class="link" href="gdk3-Cairo-Interaction.html#gdk-cairo-draw-from-gl" title="gdk_cairo_draw_from_gl ()">gdk_cairo_draw_from_gl</a> <span class="c_punctuation">()</span>
</td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect1">
<a name="gdk3-Cairo-Interaction.includes"></a><h2>Includes</h2>
<pre class="synopsis">#include &lt;gdk/gdk.h&gt;
</pre>
</div>
<div class="refsect1">
<a name="gdk3-Cairo-Interaction.description"></a><h2>Description</h2>
<p><a class="ulink" href="http://cairographics.org" target="_top">Cairo</a> is a graphics
library that supports vector graphics and image compositing that
can be used with GDK. GTK+ does all of its drawing using cairo.</p>
<p>GDK does not wrap the cairo API, instead it allows to create cairo
contexts which can be used to draw on <a href="gdk3-Windows.html#GdkWindow-struct"><span class="type">GdkWindows</span></a>. Additional
functions allow use <span class="type">GdkRectangles</span> with cairo and to use <a href="gdk3-Colors.html#GdkColor"><span class="type">GdkColors</span></a>,
<a href="gdk3-RGBA-Colors.html#GdkRGBA"><span class="type">GdkRGBAs</span></a>, <span class="type">GdkPixbufs</span> and <a href="gdk3-Windows.html#GdkWindow-struct"><span class="type">GdkWindows</span></a> as sources for drawing
operations.</p>
</div>
<div class="refsect1">
<a name="gdk3-Cairo-Interaction.functions_details"></a><h2>Functions</h2>
<div class="refsect2">
<a name="gdk-window-create-similar-surface"></a><h3>gdk_window_create_similar_surface ()</h3>
<pre class="programlisting"><a href="/usr/share/gtk-doc/html/cairo/cairo-cairo-surface-t.html#cairo-surface-t"><span class="returnvalue">cairo_surface_t</span></a> *
gdk_window_create_similar_surface (<em class="parameter"><code><a class="link" href="gdk3-Windows.html#GdkWindow"><span class="type">GdkWindow</span></a> *window</code></em>,
                                   <em class="parameter"><code><a href="/usr/share/gtk-doc/html/cairo/cairo-cairo-surface-t.html#cairo-content-t"><span class="type">cairo_content_t</span></a> content</code></em>,
                                   <em class="parameter"><code><span class="type">int</span> width</code></em>,
                                   <em class="parameter"><code><span class="type">int</span> height</code></em>);</pre>
<p>Create a new surface that is as compatible as possible with the
given <em class="parameter"><code>window</code></em>
. For example the new surface will have the same
fallback resolution and font options as <em class="parameter"><code>window</code></em>
. Generally, the new
surface will also use the same backend as <em class="parameter"><code>window</code></em>
, unless that is
not possible for some reason. The type of the returned surface may
be examined with <a href="/usr/share/gtk-doc/html/cairo/cairo-cairo-surface-t.html#cairo-surface-get-type"><code class="function">cairo_surface_get_type()</code></a>.</p>
<p>Initially the surface contents are all 0 (transparent if contents
have transparency, black otherwise.)</p>
<div class="refsect3">
<a name="gdk-window-create-similar-surface.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>window</p></td>
<td class="parameter_description"><p>window to make new surface similar to</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>content</p></td>
<td class="parameter_description"><p>the content for the new surface</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>width</p></td>
<td class="parameter_description"><p>width of the new surface</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>height</p></td>
<td class="parameter_description"><p>height of the new surface</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="gdk-window-create-similar-surface.returns"></a><h4>Returns</h4>
<p> a pointer to the newly allocated surface. The caller
owns the surface and should call <a href="/usr/share/gtk-doc/html/cairo/cairo-cairo-surface-t.html#cairo-surface-destroy"><code class="function">cairo_surface_destroy()</code></a> when done
with it.</p>
<p>This function always returns a valid pointer, but it will return a
pointer to a “nil” surface if <em class="parameter"><code>other</code></em>
is already in an error state
or any other error occurs.</p>
</div>
<p class="since">Since: 2.22</p>
</div>
<hr>
<div class="refsect2">
<a name="gdk-window-create-similar-image-surface"></a><h3>gdk_window_create_similar_image_surface ()</h3>
<pre class="programlisting"><a href="/usr/share/gtk-doc/html/cairo/cairo-cairo-surface-t.html#cairo-surface-t"><span class="returnvalue">cairo_surface_t</span></a> *
gdk_window_create_similar_image_surface
                               (<em class="parameter"><code><a class="link" href="gdk3-Windows.html#GdkWindow"><span class="type">GdkWindow</span></a> *window</code></em>,
                                <em class="parameter"><code><a href="/usr/share/gtk-doc/html/cairo/cairo-Image-Surfaces.html#cairo-format-t"><span class="type">cairo_format_t</span></a> format</code></em>,
                                <em class="parameter"><code><span class="type">int</span> width</code></em>,
                                <em class="parameter"><code><span class="type">int</span> height</code></em>,
                                <em class="parameter"><code><span class="type">int</span> scale</code></em>);</pre>
<p>Create a new image surface that is efficient to draw on the
given <em class="parameter"><code>window</code></em>
.</p>
<p>Initially the surface contents are all 0 (transparent if contents
have transparency, black otherwise.)</p>
<p>The <em class="parameter"><code>width</code></em>
 and <em class="parameter"><code>height</code></em>
 of the new surface are not affected by
the scaling factor of the <em class="parameter"><code>window</code></em>
, or by the <em class="parameter"><code>scale</code></em>
 argument; they
are the size of the surface in device pixels. If you wish to create
an image surface capable of holding the contents of <em class="parameter"><code>window</code></em>
 you can
use:</p>
<div class="informalexample">
  <table class="listing_frame" border="0" cellpadding="0" cellspacing="0">
    <tbody>
      <tr>
        <td class="listing_lines" align="right"><pre>1
2
3
4
5
6
7
8
9
10</pre></td>
        <td class="listing_code"><pre class="programlisting"><span class="kt">int</span> <span class="n">scale</span> <span class="o">=</span> <span class="n">gdk_window_get_scale_factor</span> <span class="p">(</span><span class="n">window</span><span class="p">);</span>
<span class="kt">int</span> <span class="n">width</span> <span class="o">=</span> <span class="n">gdk_window_get_width</span> <span class="p">(</span><span class="n">window</span><span class="p">)</span> <span class="o">*</span> <span class="n">scale</span><span class="p">;</span>
<span class="kt">int</span> <span class="n">height</span> <span class="o">=</span> <span class="n">gdk_window_get_height</span> <span class="p">(</span><span class="n">window</span><span class="p">)</span> <span class="o">*</span> <span class="n">scale</span><span class="p">;</span>

<span class="c1">// format is set elsewhere</span>
<span class="n">cairo_surface_t</span> <span class="o">*</span><span class="n">surface</span> <span class="o">=</span>
  <span class="n">gdk_window_create_similar_image_surface</span> <span class="p">(</span><span class="n">window</span><span class="p">,</span>
                                           <span class="n">format</span><span class="p">,</span>
                                           <span class="n">width</span><span class="p">,</span> <span class="n">height</span><span class="p">,</span>
                                           <span class="n">scale</span><span class="p">);</span></pre></td>
      </tr>
    </tbody>
  </table>
</div>

<p></p>
<p>Note that unlike <a href="/usr/share/gtk-doc/html/cairo/cairo-cairo-surface-t.html#cairo-surface-create-similar-image"><code class="function">cairo_surface_create_similar_image()</code></a>, the new
surface's device scale is set to <em class="parameter"><code>scale</code></em>
, or to the scale factor of
<em class="parameter"><code>window</code></em>
 if <em class="parameter"><code>scale</code></em>
 is 0.</p>
<div class="refsect3">
<a name="gdk-window-create-similar-image-surface.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>window</p></td>
<td class="parameter_description"><p>window to make new surface similar to, or
<code class="literal">NULL</code> if none. </p></td>
<td class="parameter_annotations"><span class="annotation">[<acronym title="NULL may be passed as the value in, out, in-out; or as a return value."><span class="acronym">nullable</span></acronym>]</span></td>
</tr>
<tr>
<td class="parameter_name"><p>format</p></td>
<td class="parameter_description"><p>the format for the new surface</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>width</p></td>
<td class="parameter_description"><p>width of the new surface</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>height</p></td>
<td class="parameter_description"><p>height of the new surface</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>scale</p></td>
<td class="parameter_description"><p>the scale of the new surface, or 0 to use same as <em class="parameter"><code>window</code></em>
</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="gdk-window-create-similar-image-surface.returns"></a><h4>Returns</h4>
<p> a pointer to the newly allocated surface. The caller
owns the surface and should call <a href="/usr/share/gtk-doc/html/cairo/cairo-cairo-surface-t.html#cairo-surface-destroy"><code class="function">cairo_surface_destroy()</code></a> when done
with it.</p>
<p>This function always returns a valid pointer, but it will return a
pointer to a “nil” surface if <em class="parameter"><code>other</code></em>
is already in an error state
or any other error occurs.</p>
</div>
<p class="since">Since: <a class="link" href="api-index-3-10.html#api-index-3.10">3.10</a></p>
</div>
<hr>
<div class="refsect2">
<a name="gdk-cairo-create"></a><h3>gdk_cairo_create ()</h3>
<pre class="programlisting"><a href="/usr/share/gtk-doc/html/cairo/cairo-cairo-t.html#cairo-t"><span class="returnvalue">cairo_t</span></a> *
gdk_cairo_create (<em class="parameter"><code><a class="link" href="gdk3-Windows.html#GdkWindow"><span class="type">GdkWindow</span></a> *window</code></em>);</pre>
<div class="warning">
<p><code class="literal">gdk_cairo_create</code> has been deprecated since version 3.22 and should not be used in newly-written code.</p>
<p>Use <a class="link" href="gdk3-Windows.html#gdk-window-begin-draw-frame" title="gdk_window_begin_draw_frame ()"><code class="function">gdk_window_begin_draw_frame()</code></a> and
  <a class="link" href="GdkDrawingContext.html#gdk-drawing-context-get-cairo-context" title="gdk_drawing_context_get_cairo_context ()"><code class="function">gdk_drawing_context_get_cairo_context()</code></a> instead</p>
</div>
<p>Creates a Cairo context for drawing to <em class="parameter"><code>window</code></em>
.</p>
<p>Note that calling <a href="/usr/share/gtk-doc/html/cairo/cairo-cairo-t.html#cairo-reset-clip"><code class="function">cairo_reset_clip()</code></a> on the resulting <a href="/usr/share/gtk-doc/html/cairo/cairo-cairo-t.html#cairo-t"><span class="type">cairo_t</span></a> will
produce undefined results, so avoid it at all costs.</p>
<p>Typically, this function is used to draw on a <a class="link" href="gdk3-Windows.html#GdkWindow"><span class="type">GdkWindow</span></a> out of the paint
cycle of the toolkit; this should be avoided, as it breaks various assumptions
and optimizations.</p>
<p>If you are drawing on a native <a class="link" href="gdk3-Windows.html#GdkWindow"><span class="type">GdkWindow</span></a> in response to a <a class="link" href="gdk3-Events.html#GDK-EXPOSE:CAPS"><code class="literal">GDK_EXPOSE</code></a> event
you should use <a class="link" href="gdk3-Windows.html#gdk-window-begin-draw-frame" title="gdk_window_begin_draw_frame ()"><code class="function">gdk_window_begin_draw_frame()</code></a> and <a class="link" href="GdkDrawingContext.html#gdk-drawing-context-get-cairo-context" title="gdk_drawing_context_get_cairo_context ()"><code class="function">gdk_drawing_context_get_cairo_context()</code></a>
instead. GTK will automatically do this for you when drawing a widget.</p>
<div class="refsect3">
<a name="gdk-cairo-create.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>window</p></td>
<td class="parameter_description"><p>a <a class="link" href="gdk3-Windows.html#GdkWindow"><span class="type">GdkWindow</span></a></p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="gdk-cairo-create.returns"></a><h4>Returns</h4>
<p> A newly created Cairo context. Free with
<a href="/usr/share/gtk-doc/html/cairo/cairo-cairo-t.html#cairo-destroy"><code class="function">cairo_destroy()</code></a> when you are done drawing.</p>
</div>
<p class="since">Since: 2.8</p>
</div>
<hr>
<div class="refsect2">
<a name="gdk-cairo-get-clip-rectangle"></a><h3>gdk_cairo_get_clip_rectangle ()</h3>
<pre class="programlisting"><span class="returnvalue">gboolean</span>
gdk_cairo_get_clip_rectangle (<em class="parameter"><code><a href="/usr/share/gtk-doc/html/cairo/cairo-cairo-t.html#cairo-t"><span class="type">cairo_t</span></a> *cr</code></em>,
                              <em class="parameter"><code><a class="link" href="gdk3-Points-Rectangles-and-Regions.html#GdkRectangle" title="GdkRectangle"><span class="type">GdkRectangle</span></a> *rect</code></em>);</pre>
<p>This is a convenience function around <a href="/usr/share/gtk-doc/html/cairo/cairo-cairo-t.html#cairo-clip-extents"><code class="function">cairo_clip_extents()</code></a>.
It rounds the clip extents to integer coordinates and returns
a boolean indicating if a clip area exists.</p>
<div class="refsect3">
<a name="gdk-cairo-get-clip-rectangle.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>cr</p></td>
<td class="parameter_description"><p>a cairo context</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>rect</p></td>
<td class="parameter_description"><p>return location for the clip, or <code class="literal">NULL</code>. </p></td>
<td class="parameter_annotations"><span class="annotation">[<acronym title="Parameter for returning results. Default is transfer full."><span class="acronym">out</span></acronym>][<acronym title="NULL is OK, both for passing and for returning."><span class="acronym">allow-none</span></acronym>]</span></td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="gdk-cairo-get-clip-rectangle.returns"></a><h4>Returns</h4>
<p> <code class="literal">TRUE</code> if a clip rectangle exists, <code class="literal">FALSE</code> if all of <em class="parameter"><code>cr</code></em>
is
clipped and all drawing can be skipped</p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="gdk-cairo-get-drawing-context"></a><h3>gdk_cairo_get_drawing_context ()</h3>
<pre class="programlisting"><a class="link" href="GdkDrawingContext.html" title="GdkDrawingContext"><span class="returnvalue">GdkDrawingContext</span></a> *
gdk_cairo_get_drawing_context (<em class="parameter"><code><a href="/usr/share/gtk-doc/html/cairo/cairo-cairo-t.html#cairo-t"><span class="type">cairo_t</span></a> *cr</code></em>);</pre>
<p>Retrieves the <a class="link" href="GdkDrawingContext.html" title="GdkDrawingContext"><span class="type">GdkDrawingContext</span></a> that created the Cairo
context <em class="parameter"><code>cr</code></em>
.</p>
<div class="refsect3">
<a name="gdk-cairo-get-drawing-context.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>cr</p></td>
<td class="parameter_description"><p>a Cairo context</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="gdk-cairo-get-drawing-context.returns"></a><h4>Returns</h4>
<p>a <a class="link" href="GdkDrawingContext.html" title="GdkDrawingContext"><span class="type">GdkDrawingContext</span></a>, if any is set. </p>
<p><span class="annotation">[<acronym title="The data is owned by the callee, which is responsible of freeing it."><span class="acronym">transfer none</span></acronym>][<acronym title="NULL may be passed as the value in, out, in-out; or as a return value."><span class="acronym">nullable</span></acronym>]</span></p>
</div>
<p class="since">Since: <a class="link" href="api-index-3-22.html#api-index-3.22">3.22</a></p>
</div>
<hr>
<div class="refsect2">
<a name="gdk-cairo-set-source-color"></a><h3>gdk_cairo_set_source_color ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span>
gdk_cairo_set_source_color (<em class="parameter"><code><a href="/usr/share/gtk-doc/html/cairo/cairo-cairo-t.html#cairo-t"><span class="type">cairo_t</span></a> *cr</code></em>,
                            <em class="parameter"><code>const <a class="link" href="gdk3-Colors.html#GdkColor" title="GdkColor"><span class="type">GdkColor</span></a> *color</code></em>);</pre>
<div class="warning">
<p><code class="literal">gdk_cairo_set_source_color</code> has been deprecated since version 3.4 and should not be used in newly-written code.</p>
<p>Use <a class="link" href="gdk3-Cairo-Interaction.html#gdk-cairo-set-source-rgba" title="gdk_cairo_set_source_rgba ()"><code class="function">gdk_cairo_set_source_rgba()</code></a> instead</p>
</div>
<p>Sets the specified <a class="link" href="gdk3-Colors.html#GdkColor" title="GdkColor"><span class="type">GdkColor</span></a> as the source color of <em class="parameter"><code>cr</code></em>
.</p>
<div class="refsect3">
<a name="gdk-cairo-set-source-color.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>cr</p></td>
<td class="parameter_description"><p>a cairo context</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>color</p></td>
<td class="parameter_description"><p>a <a class="link" href="gdk3-Colors.html#GdkColor" title="GdkColor"><span class="type">GdkColor</span></a></p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<p class="since">Since: 2.8</p>
</div>
<hr>
<div class="refsect2">
<a name="gdk-cairo-set-source-rgba"></a><h3>gdk_cairo_set_source_rgba ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span>
gdk_cairo_set_source_rgba (<em class="parameter"><code><a href="/usr/share/gtk-doc/html/cairo/cairo-cairo-t.html#cairo-t"><span class="type">cairo_t</span></a> *cr</code></em>,
                           <em class="parameter"><code>const <a class="link" href="gdk3-RGBA-Colors.html#GdkRGBA" title="GdkRGBA"><span class="type">GdkRGBA</span></a> *rgba</code></em>);</pre>
<p>Sets the specified <a class="link" href="gdk3-RGBA-Colors.html#GdkRGBA" title="GdkRGBA"><span class="type">GdkRGBA</span></a> as the source color of <em class="parameter"><code>cr</code></em>
.</p>
<div class="refsect3">
<a name="gdk-cairo-set-source-rgba.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>cr</p></td>
<td class="parameter_description"><p>a cairo context</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>rgba</p></td>
<td class="parameter_description"><p>a <a class="link" href="gdk3-RGBA-Colors.html#GdkRGBA" title="GdkRGBA"><span class="type">GdkRGBA</span></a></p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<p class="since">Since: <a class="link" href="api-index-3-0.html#api-index-3.0">3.0</a></p>
</div>
<hr>
<div class="refsect2">
<a name="gdk-cairo-set-source-pixbuf"></a><h3>gdk_cairo_set_source_pixbuf ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span>
gdk_cairo_set_source_pixbuf (<em class="parameter"><code><a href="/usr/share/gtk-doc/html/cairo/cairo-cairo-t.html#cairo-t"><span class="type">cairo_t</span></a> *cr</code></em>,
                             <em class="parameter"><code>const <span class="type">GdkPixbuf</span> *pixbuf</code></em>,
                             <em class="parameter"><code><span class="type">gdouble</span> pixbuf_x</code></em>,
                             <em class="parameter"><code><span class="type">gdouble</span> pixbuf_y</code></em>);</pre>
<p>Sets the given pixbuf as the source pattern for <em class="parameter"><code>cr</code></em>
.</p>
<p>The pattern has an extend mode of <a href="/usr/share/gtk-doc/html/cairo/cairo-cairo-pattern-t.html#CAIRO-EXTEND-NONE:CAPS"><code class="literal">CAIRO_EXTEND_NONE</code></a> and is aligned
so that the origin of <em class="parameter"><code>pixbuf</code></em>
 is <em class="parameter"><code>pixbuf_x</code></em>
, <em class="parameter"><code>pixbuf_y</code></em>
.</p>
<div class="refsect3">
<a name="gdk-cairo-set-source-pixbuf.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>cr</p></td>
<td class="parameter_description"><p>a cairo context</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>pixbuf</p></td>
<td class="parameter_description"><p>a <span class="type">GdkPixbuf</span></p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>pixbuf_x</p></td>
<td class="parameter_description"><p>X coordinate of location to place upper left corner of <em class="parameter"><code>pixbuf</code></em>
</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>pixbuf_y</p></td>
<td class="parameter_description"><p>Y coordinate of location to place upper left corner of <em class="parameter"><code>pixbuf</code></em>
</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<p class="since">Since: 2.8</p>
</div>
<hr>
<div class="refsect2">
<a name="gdk-cairo-set-source-window"></a><h3>gdk_cairo_set_source_window ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span>
gdk_cairo_set_source_window (<em class="parameter"><code><a href="/usr/share/gtk-doc/html/cairo/cairo-cairo-t.html#cairo-t"><span class="type">cairo_t</span></a> *cr</code></em>,
                             <em class="parameter"><code><a class="link" href="gdk3-Windows.html#GdkWindow"><span class="type">GdkWindow</span></a> *window</code></em>,
                             <em class="parameter"><code><span class="type">gdouble</span> x</code></em>,
                             <em class="parameter"><code><span class="type">gdouble</span> y</code></em>);</pre>
<p>Sets the given window as the source pattern for <em class="parameter"><code>cr</code></em>
.</p>
<p>The pattern has an extend mode of <a href="/usr/share/gtk-doc/html/cairo/cairo-cairo-pattern-t.html#CAIRO-EXTEND-NONE:CAPS"><code class="literal">CAIRO_EXTEND_NONE</code></a> and is aligned
so that the origin of <em class="parameter"><code>window</code></em>
 is <em class="parameter"><code>x</code></em>
, <em class="parameter"><code>y</code></em>
. The window contains all its
subwindows when rendering.</p>
<p>Note that the contents of <em class="parameter"><code>window</code></em>
 are undefined outside of the
visible part of <em class="parameter"><code>window</code></em>
, so use this function with care.</p>
<div class="refsect3">
<a name="gdk-cairo-set-source-window.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>cr</p></td>
<td class="parameter_description"><p>a cairo context</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>window</p></td>
<td class="parameter_description"><p>a <a class="link" href="gdk3-Windows.html#GdkWindow"><span class="type">GdkWindow</span></a></p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>x</p></td>
<td class="parameter_description"><p>X coordinate of location to place upper left corner of <em class="parameter"><code>window</code></em>
</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>y</p></td>
<td class="parameter_description"><p>Y coordinate of location to place upper left corner of <em class="parameter"><code>window</code></em>
</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<p class="since">Since: 2.24</p>
</div>
<hr>
<div class="refsect2">
<a name="gdk-cairo-rectangle"></a><h3>gdk_cairo_rectangle ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span>
gdk_cairo_rectangle (<em class="parameter"><code><a href="/usr/share/gtk-doc/html/cairo/cairo-cairo-t.html#cairo-t"><span class="type">cairo_t</span></a> *cr</code></em>,
                     <em class="parameter"><code>const <a class="link" href="gdk3-Points-Rectangles-and-Regions.html#GdkRectangle" title="GdkRectangle"><span class="type">GdkRectangle</span></a> *rectangle</code></em>);</pre>
<p>Adds the given rectangle to the current path of <em class="parameter"><code>cr</code></em>
.</p>
<div class="refsect3">
<a name="gdk-cairo-rectangle.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>cr</p></td>
<td class="parameter_description"><p>a cairo context</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>rectangle</p></td>
<td class="parameter_description"><p>a <a class="link" href="gdk3-Points-Rectangles-and-Regions.html#GdkRectangle" title="GdkRectangle"><span class="type">GdkRectangle</span></a></p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<p class="since">Since: 2.8</p>
</div>
<hr>
<div class="refsect2">
<a name="gdk-cairo-region"></a><h3>gdk_cairo_region ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span>
gdk_cairo_region (<em class="parameter"><code><a href="/usr/share/gtk-doc/html/cairo/cairo-cairo-t.html#cairo-t"><span class="type">cairo_t</span></a> *cr</code></em>,
                  <em class="parameter"><code>const <a href="/usr/share/gtk-doc/html/cairo/cairo-Regions.html#cairo-region-t"><span class="type">cairo_region_t</span></a> *region</code></em>);</pre>
<p>Adds the given region to the current path of <em class="parameter"><code>cr</code></em>
.</p>
<div class="refsect3">
<a name="gdk-cairo-region.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>cr</p></td>
<td class="parameter_description"><p>a cairo context</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>region</p></td>
<td class="parameter_description"><p>a <a href="/usr/share/gtk-doc/html/cairo/cairo-Regions.html#cairo-region-t"><span class="type">cairo_region_t</span></a></p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<p class="since">Since: 2.8</p>
</div>
<hr>
<div class="refsect2">
<a name="gdk-cairo-region-create-from-surface"></a><h3>gdk_cairo_region_create_from_surface ()</h3>
<pre class="programlisting"><a href="/usr/share/gtk-doc/html/cairo/cairo-Regions.html#cairo-region-t"><span class="returnvalue">cairo_region_t</span></a> *
gdk_cairo_region_create_from_surface (<em class="parameter"><code><a href="/usr/share/gtk-doc/html/cairo/cairo-cairo-surface-t.html#cairo-surface-t"><span class="type">cairo_surface_t</span></a> *surface</code></em>);</pre>
<p>Creates region that describes covers the area where the given
<em class="parameter"><code>surface</code></em>
 is more than 50% opaque.</p>
<p>This function takes into account device offsets that might be
set with <a href="/usr/share/gtk-doc/html/cairo/cairo-cairo-surface-t.html#cairo-surface-set-device-offset"><code class="function">cairo_surface_set_device_offset()</code></a>.</p>
<div class="refsect3">
<a name="gdk-cairo-region-create-from-surface.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>surface</p></td>
<td class="parameter_description"><p>a cairo surface</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="gdk-cairo-region-create-from-surface.returns"></a><h4>Returns</h4>
<p> A <a href="/usr/share/gtk-doc/html/cairo/cairo-Regions.html#cairo-region-t"><span class="type">cairo_region_t</span></a>; must be freed with <a href="/usr/share/gtk-doc/html/cairo/cairo-Regions.html#cairo-region-destroy"><code class="function">cairo_region_destroy()</code></a></p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="gdk-cairo-surface-create-from-pixbuf"></a><h3>gdk_cairo_surface_create_from_pixbuf ()</h3>
<pre class="programlisting"><a href="/usr/share/gtk-doc/html/cairo/cairo-cairo-surface-t.html#cairo-surface-t"><span class="returnvalue">cairo_surface_t</span></a> *
gdk_cairo_surface_create_from_pixbuf (<em class="parameter"><code>const <span class="type">GdkPixbuf</span> *pixbuf</code></em>,
                                      <em class="parameter"><code><span class="type">int</span> scale</code></em>,
                                      <em class="parameter"><code><a class="link" href="gdk3-Windows.html#GdkWindow"><span class="type">GdkWindow</span></a> *for_window</code></em>);</pre>
<p>Creates an image surface with the same contents as
the pixbuf.</p>
<div class="refsect3">
<a name="gdk-cairo-surface-create-from-pixbuf.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>pixbuf</p></td>
<td class="parameter_description"><p>a <span class="type">GdkPixbuf</span></p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>scale</p></td>
<td class="parameter_description"><p>the scale of the new surface, or 0 to use same as <em class="parameter"><code>window</code></em>
</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>for_window</p></td>
<td class="parameter_description"><p>The window this will be drawn to, or <code class="literal">NULL</code>. </p></td>
<td class="parameter_annotations"><span class="annotation">[<acronym title="NULL is OK, both for passing and for returning."><span class="acronym">allow-none</span></acronym>]</span></td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="gdk-cairo-surface-create-from-pixbuf.returns"></a><h4>Returns</h4>
<p> a new cairo surface, must be freed with <a href="/usr/share/gtk-doc/html/cairo/cairo-cairo-surface-t.html#cairo-surface-destroy"><code class="function">cairo_surface_destroy()</code></a></p>
</div>
<p class="since">Since: <a class="link" href="api-index-3-10.html#api-index-3.10">3.10</a></p>
</div>
<hr>
<div class="refsect2">
<a name="gdk-cairo-draw-from-gl"></a><h3>gdk_cairo_draw_from_gl ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span>
gdk_cairo_draw_from_gl (<em class="parameter"><code><a href="/usr/share/gtk-doc/html/cairo/cairo-cairo-t.html#cairo-t"><span class="type">cairo_t</span></a> *cr</code></em>,
                        <em class="parameter"><code><a class="link" href="gdk3-Windows.html#GdkWindow"><span class="type">GdkWindow</span></a> *window</code></em>,
                        <em class="parameter"><code><span class="type">int</span> source</code></em>,
                        <em class="parameter"><code><span class="type">int</span> source_type</code></em>,
                        <em class="parameter"><code><span class="type">int</span> buffer_scale</code></em>,
                        <em class="parameter"><code><span class="type">int</span> x</code></em>,
                        <em class="parameter"><code><span class="type">int</span> y</code></em>,
                        <em class="parameter"><code><span class="type">int</span> width</code></em>,
                        <em class="parameter"><code><span class="type">int</span> height</code></em>);</pre>
<p>This is the main way to draw GL content in GTK+. It takes a render buffer ID 
(<em class="parameter"><code>source_type</code></em>
 == <span class="type">GL_RENDERBUFFER</span>) or a texture id (<em class="parameter"><code>source_type</code></em>
 == <span class="type">GL_TEXTURE</span>)
and draws it onto <em class="parameter"><code>cr</code></em>
 with an OVER operation, respecting the current clip.
The top left corner of the rectangle specified by <em class="parameter"><code>x</code></em>
, <em class="parameter"><code>y</code></em>
, <em class="parameter"><code>width</code></em>
 and <em class="parameter"><code>height</code></em>

will be drawn at the current (0,0) position of the cairo_t.</p>
<p>This will work for *all* cairo_t, as long as <em class="parameter"><code>window</code></em>
 is realized, but the
fallback implementation that reads back the pixels from the buffer may be
used in the general case. In the case of direct drawing to a window with
no special effects applied to <em class="parameter"><code>cr</code></em>
 it will however use a more efficient
approach.</p>
<p>For <span class="type">GL_RENDERBUFFER</span> the code will always fall back to software for buffers
with alpha components, so make sure you use <span class="type">GL_TEXTURE</span> if using alpha.</p>
<p>Calling this may change the current GL context.</p>
<div class="refsect3">
<a name="gdk-cairo-draw-from-gl.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>cr</p></td>
<td class="parameter_description"><p>a cairo context</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>window</p></td>
<td class="parameter_description"><p>The window we're rendering for (not necessarily into)</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>source</p></td>
<td class="parameter_description"><p>The GL ID of the source buffer</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>source_type</p></td>
<td class="parameter_description"><p>The type of the <em class="parameter"><code>source</code></em>
</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>buffer_scale</p></td>
<td class="parameter_description"><p>The scale-factor that the <em class="parameter"><code>source</code></em>
buffer is allocated for</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>x</p></td>
<td class="parameter_description"><p>The source x position in <em class="parameter"><code>source</code></em>
to start copying from in GL coordinates</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>y</p></td>
<td class="parameter_description"><p>The source y position in <em class="parameter"><code>source</code></em>
to start copying from in GL coordinates</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>width</p></td>
<td class="parameter_description"><p>The width of the region to draw</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>height</p></td>
<td class="parameter_description"><p>The height of the region to draw</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<p class="since">Since: <a class="link" href="api-index-3-16.html#api-index-3.16">3.16</a></p>
</div>
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